With the second series of the breathtaking show taking 10 years to produce, it wouldn't be inconceivable that David Attenborough could be producing the show up until his centenary in 2026.

The huge success of the most recent series of Planet Earth prompted BBC bosses to start talking about a third series, and Britain's Daily Star newspaper reports that executives are keen to get started on production as soon as possible.

Producer Mike Gunton told the publication that it is going to take some time to put together a third series, but he is hopeful it will happen.

"We'd also be crazy to say it will be here in three years or even five years' time," he said. "We love working with Sir David and I think he loves working with us, and we want that to last as long as possible."

Gunton also said the programme would likely come to a natural end if Attenborough ever decided to step down as host. The television legend has become synonymous with the show, with Gunton admitting they would fail to find a replacement that could fill his shoes.

"When he decides he doesn't want to do any more, we will have to rethink how we make these programmes," he said. "You can't replace him - it's pointless trying."

The second series of Planet Earth came to an end on Monday night, with Attenborough making an emotional plea for people to do more to save nature and look after our world in his sign-off.

Speaking to the camera as he stood atop a London skyscraper, Attenborough said: "Looking down on this great metropolis, the ingenuity with which we continue to reshape the surface of our planet is very striking. And it's also sobering. It reminds me of just how easy it is for us to lose our connection with the natural world. Yet it's on this connection that the future of both humanity and the natural world will depend.

"It's surely our responsibility to do everything within our power to create a planet that provides a home not just for us, but for all life on Earth."